What is the significance of the Nyquist frequency?

The Nyquist frequency is significant because it defines the highest frequency that can be accurately sampled according to the Nyquist-Shannon sampling theorem. This theorem states that in order to digitally capture a signal without losing any information, the sampling rate must be at least twice the highest frequency present in the signal. Therefore, the Nyquist frequency is essentially half of the sampling rate. If frequencies higher than the Nyquist frequency are present in the signal, they can lead to an effect known as aliasing, where higher frequencies are misrepresented as lower frequencies, resulting in distortion. Understanding the Nyquist frequency is crucial for audio engineers and anyone involved in signal processing, as it directly impacts the fidelity and clarity of captured audio.